Baffle-plate arrangement for concrete mixers



H. P. PARIS 1,723,367

BAFFLE PLATE ARRANGEMENT FOR CONCRETE MIXEHS Aug. 6, 1929.

2 Sheets-Sheet Filed Nov. 1, 1927 Fig.1.

1521 6276 on flag/"2 ,Pamls,

Aug. 6, 1929. R P I 1,723,367

BAEFLE PLATE ARRANGEMENT FOR CONCRETE MIXERS Filed Nov. 1, 1927 2Sheets-Sheet 2 Patented Aug. 6, 1929.

UNITED STATES 1,723,367 PATENT OFFICE.

HUG-H P. IARIS, QF KING COUNTY, NEAR KIRKLAND, WASHINGTON, ASSIGNOR TOPARIS TRANSIT MIXER COMPANY, OF SEATTLE, WASHINGTON, A CORPORATION OF.WASHINGTON.

RAFFLE-PLATE ARRANGEMENT FOR CONCRETE MIXERSL Application filed NovemberThis invention relates generally to rotatable mixing devices wherein thematerial to be mixed is contained within a rotatable mixing shell andwhile contained therein is, by the rotation of the shell and the actionof mixing blades thereon, intermixed into a homogeneous mass.

, The invention is more particularly directed to the construction andarrangement and edge formation of mixing blades or baflie plates foracting on the material while contained and agitated in the rotatingshell.

The invent-ion has for its principal object to provide a novel form ofbaffle plate or mixing blade, one edge of which is provided withprotuberances or recessed portions affording a greater length to theedge surface of the blade than is present in the length of the blade; toprovide a structure wherein the protuberances or recesses do notmaterially weaken the blade structure, and which increased length of theouter edge of the blade affords a greater slumping or spilling edgesurface for the blade than if the edge were a straight Another andimportant object is to arrange blades of this type or baflie plateswithin the cylinder or'shell with the protuberancesof the adjacentblades in staggered relation, preferably with the recessed portions ofone blade in the path of rotation of the protuberances of the adjacentblade, affording a means whereby the mass of concrete or material to bemixed that passes through the recessed por tion of one blade or plate isacted on by the protuberances of the next blade or plate,causing aquicker mixing of the ingredients at a lower gravity, requiring lesspower over the straight edge plate now universally in use. 40 With theabove mentioned and other objects in view, the invention consists in thenovel construction and combination of parts hereinafter described,illustrated in the ac-- companying drawings and pointed out in theclaims hereto appended; it being understood that various changes in theform, proportion, size and minor details of construction within thescope of the claim may be resorted to without departing from the spiritor sacrificing any of the advantages of the invention.

In the drawings disclosing one embodiment of my invention Fig. 1 is aview in plan of the inner surface of a mixer shell as the same wouldappear if 1, 1927- Serial No. 230,237.

cut longitudinally and rolled flat, the mixing blades or baffle platesbeing illustrated as secured to the inner face thereof, in theirpreferred arrangement.

Fig. 2 is a transverse sectional view through the shell, illustratingthe spacing of the baffle plates or blades.

Fig. 3 is afragmentary view in perspective, illustrating three baffleplates or blades in their preferred arrangement on the interior Wallsurface of the mixer shell with their cutout or irregular edges instaggered relationship, and also illustrating one form of mountifng forsecuring the blades to the shell sur ace.

In the drawings, wherein like characters of reference designatecorresponding parts in the several views 1 represents a mixing shell ofcylindrical formation, provided at one end with an outlet 2, the shellbeing preferably mounted in a manner not illustrated, to rotate on alongitudinal axis, as, forexample, on the line Mounted on the inner wallsurface of the member 1, and illustrated as projecting radiallytherefrom toward the axis of rotation of the shell, are a plurality ofbattle plates or mixing blades 3. The blades or plates are arrangedpreferably in the series C, D and E, circumferentially of the interiorof the shell. The blades of the series D are preferably disposedparallel with the axis of rotation of the cylinder, with their ends inrelative staggered relation, and the blades parallel spaced. The seriesC and E are preferably positioned at opposite ends of the cylinder, oneat either end of the series of blades D; the blades of these series 0and E being disposed 'pref- I erably in parallel spaced relationobliquely to the axis of rotation of the cylinder, the angle ofdisposition of the series E being reverse to that of the series G, andthe ends of the blades of the respective series being preferably instaggered relation, as illustrated.

The angular disposition of the blades of the series C and E acts on thematerial to be mixed in such manner that on the rotation of thecylinder, the. material picked up by the blades of these respectiveseries is discharged therefrom toward the transverse center of the shellor cylinder, to be acted on by the blades of series thus the material inaddition to being agitated-by the axial rotation of the cylinder orshell, is discharged from the blades at an an le to the axis of rotationof the cylinder. orresponding blades of the series C, D and E arearranged in end to end relation, afiording between each row anunobstructed passage l5, which admits of the sliding or slipping of thematerial or its free passage endwise of the cylinder or shell when thesame is moved to a dumping position, which preferably is at an inclinefrom the horizontal toward the discharge opening 2. Each blade asclearly illustrated in Fi 3 is preferably of flat plate or sheetconstruction, formed with a straight inner edge a and an irregular outeredge 5. As illustrated, the irregularity in the outer edge is formed bythe projections or protuberances 6, separated by depressions 7,afiording an outer edge 8 of a greater length than that of the inneredge 4, which is the length of the blades 3.

By forming the mixing or outer edge of the blades irregular, l havediscovered that as these blades or baffle plates lift the material to bemixed as the cylinder rotates, the material resting thereon-slumps orslides oil this edge surface of greater length than the blade, which inthe present illustration is approximately greater than the length of theblade, producing a more thorough mixing in a shorter period of time. 7

By this blade edge construction, I have discovered that during therotation of the cylinder any dried lumps of aggregate lifted thereby aremore thoroughly broken up when passing lmom the edge of the irregularblade than is the casewhen a straight edge blade is used.

Each blade is secured to the inner surface of the shell or mixing drum,with its inner edge l in spaced relation to the shell surface,

and while 1 have illustrated attaching angle brackets 9 secured to theside faces thereof, it is to be understood that these may be in the formof integral extensions.

The spacing of the inner edge of the mixing blades or baffle plates fromthe inner surface of the shell affords a relatively narrow passage 10between the inner edge of the blade and the inner shell surface throughwhich small quantities of the mixed aggregates may pass during themining operation. This spacing also affords a means to assist in theilow of Water orother fluid around the inanswer her edge surface of theshell when it is de sired to clean or Wash the same.

As illustrated in Fig. 3, the protuberances 6 and depressions 7 ofadjacent blades of any given series are preferably arranged in staggeredrelation.

The arrangement of the bullies or blades with their portions 6 and 7 instaggered relation circumferentially of the axis of rotation of thecylinder, enables successive blades to out upwardly to difierent levelsinto the mass resting in the cylinder, removing from the mass quantitiesof material of uneven thickness, the material passing through therecessed portion of one plate being picked up by the protuberances ofthe plate immediately following. This action takes place during theentire operation of the cylinder, causing a wave formation in the baseof the mass of concrete in the shell.

T he formation of the mixer blades or bafilc plates as illustrated anddescribed with an uneven edge, enables the material picked up by theblades to partially slump from its edge almost immediately on the bladeclearing the mass. This increases the mixing action andcorrespondinglyreduces the side load action on the cylinder over theside load action present when straight edge blades are employed.

1 claim in combination With a mixing cylinder, a plurality of mixingblades disposed edgewise in rows circumferentially of the interiorthereof With the adjacent ends of corresponding blades of adjacent rowsin overlapping relation circumferentially of the cylinder, the outer,edge of each blade provided with re cessed portions afiordingprotrusions separating the same, the blades of the respective rows lyingin parallel spaced relation with the protrusions of one blade lyingwithin the path of travel of the recessed portions of a succeedingblade, and angle brackets extending from the inner edge of each bladefor independently attaching the same to the inner surface of thecylinder with the inner blade edge spaced therefrom aifording a passagecircumferentially of the entire inner surface of the cylinderunobstructed except for the blade attaching means.

ln testimony whereof I have signed my name to this specification.

HUGH PAR-1S.

